Method of treating beer or ale.



METHOD OF TREATING BEER OR ALE.

Specificationof Letters Patent. Patented June 20, 1911.

No Drawing. Original application filed April 11, 1910, Serial No. 554,645. Divided and this application filed April 8, 1911.

Serial No. 619,675.

To all whom it may concern:

Be it known that I, LEO VVALIERSTEIN, a subject of the Emperor of Germany, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Methods'of Treating Beer or Ale, of which the following is a specification.

This invention relates to the preparation of beers and ales, and more particularly to the preparation of improvedbottled beers, the object of the invention being the production of bottled beers which possess great clear and brilliant for some time if placed upon ice directly after bottling. The same beers however, after pasteurization, are far less resistant to cold and usually cloud or become turbid when placed on ice. This sensitiveness to cold becomes more pro.- nounced after the beers have been bottled for some time, and in many cases it isfound that the beer not only clouds when chilled,

but the bottles show a sediment consisting The mainly of precipitated proteid matter. probable reason fortheclouding of chilled pasteurized beers is that during the pasteurization a part of the proteids contained'in I the beer are so modified thatv they become insoluble-upon chilling, thereby causing turbidity. r

According to the present process there is added to'the beer at any suitable stage of the brewing, that is to say at any period subsequent to the cooling of the wort, and

usually after the conclusion of the main fermentation," a proportion of proteolytic enzyms active in slightlchillproof'in the sensethat it is capable of remaining brilliant even when kept upon ice for a considerable time; In'practice it has been found advantageous in most cases to acid media sufficient to modify the proteids contained in the add the enzyms to the clarified beer shortly before bottling. Durin the pasteurization which follows the bottling, the enzyms become active, and those proteids which would cloud the beer when chilled are so modified by the proteo-lysis that the resulting beer will remain clear and brilliant, being no longer sensitive to cold. Beers and ales treated in accordance with this invention have beenfound to be substantially unaffected by exposureto diffused daylight for 7 days or even weeks, and comparatively little affected even by the direct rays of the sun, whereas untreated beers, as is well known, rapidly acquire. a iighly disagreeable odor and flavor when exposed to sunlight, and quickly lose their brilliance, often depositinga sediment, under the action of difiused daylight. I have also found that if the proteolyt-ic enzyms be added in suflicient quantity, and if excessive'temperatures are not used during pasteurization, the enzyms remain active afterpasteurization. 'By their activity subsequent to pasteurization they exert a further beneficial influence, inas- Inuch as they are foundto'have a'pept-onizing effect upon the proteids while the bottled beer is stored at ordinary temperatures. This fact is of particular advantage in the case of beers which are to be shipped long distances or stored in bottles for long periods, or which are required to undergo climatic changes; for such treatment, as is well known, increases greatly the sensitiveness of bottled beers with respect to cold and even produces a sediment in the bottles. The above described peptonization occurring at ordinary temperatures in the bottles is found however to impart to the beer the capability of enduring long storage, transportation or climatic change without becomteolytic enzyms which-are suited for use in accordance with this invention, or to state a definite proportion in which each should be added. Enzyms which are suitable for the purpose above described are widely d1s'- 't'ribu'ted in. the vegetable and animal kingdoms, are readily prepared in. concentrated form by-known methods, and their'preparations have several instances become standard articles of commerce. Such preparations are not however .pure in the sense of ."consisting solely of enzyms or of a single .enzym, and "all .prqteolyt-ic enzyms are in. practice recognized only by their efiects upon proteid matter. The source from which proteolytic enzyms are derived is not 5 material or important, provided the preparation is free from constituents injurious to the beer and the enzyms are capable of exerting the proper modifying action upon the proteids under the conditions existing in beers or ales durin or after pasteurization. The enzyms se ected should-be such as are capable of inducing proteolysis in slightlyv acid liquids, and such as are not destroyed or rendered permanently inactive by subjection to the usual temperatures of pasteurization. The activity of enzyms from various sources difiers greatly, their activity beingwalso afiected by their mode of preparation or concentration; and inasmuch as the proportion or quantity to be used is dependent upon their activity, it is evident that such proportion or quantity can be specified only in particular cases, being however readily determined by simple test for each case.

Enzyms which are suited for use in ac- .cordance with this invention may be prepared from malt by known methods; (com-' pare for example Fernbach and Hubert, .ompt. Re'nd. de ZAcad. des Sciences, 1900, "130, 1783; 131, 293; Windisch and Schellhorn, Wochensch. Bram, 1900, 17, 334; and Weiss, Oompt. Rend.- Tran. Laborat. Carlsberg, 1903, 5,135). I have also been able to prepare an enzym capable of producing the above described efiects upon beer in accordance with the following method: Green malt which has been permitted to grow for 'a period of one to two weeks according to conditions, is finely ground, preferably with the addition of quartz sand. The ground product is saturated with a solution containing 0.1 to 0.3 per cent. of hydrochlorig acid and is permitted to stand at room tem- -,peratures for twelve to twenty-four hours. The, acid -liquid is then expressed under heavy pressure, and is mixed with several volumes of stron alcohol. precipitate contains the enzym, vand is quickly separated'from the liquid and dried in vacuo at temperatures not exceedingi40 C. It should be clearly understood that these enzyms are extremely sensitive to physicaland 'chemical conditions,. and may be rendered inactive by factors .the presence of which it is often 'difiicult or impossible to recognize. Hence it may occur that the preparations made under seemingly identical conditions may differ widely in their activity or in their suitability for the purposes of this, invention. Hence the preparations should in all cases-be tested as to their effects upon been before using them.

Besides the'peptase prepared from nialt, preparations containing proteolytic enzyms The resulting from other sources are well adapted for use,

provided only they are active in slightly acid media and are free from substancesinjurious to the beer. Thus I may mention by way of example papain, der1ved= from papaw, bromelin, from the fruit of the pme- .gpple (see Biochem'ie d61- Pflanzen, .Czapek,

ena, 1905, Volume II, p. 167), and pepsin,

from the gastric secretions of mammals. Those commercial preparations of papain and pepsin which exhibit a comparatively high de ree of activity, say in excess of 123000 that is to say which are capable under the standard conditions recited in the U. S. PhdWTbMOpZiti of digestingat least 3000 times their weight of freshly c0- agulated egg-albumen) have been found to be suitable for the purposes of this invention. It should be understood that zymogens convertible into proteolytic enzyms may serve as additions to the beer, givin rise therein to the'respective enzyms.- Wit ref erence to' epsin, it is commonly stated that this enzynii is rapidly destroyed by warming to .5557 0.: I have found however that under the conditions obtaining during pass teurlza-tlon of beer at temperatures of 57-,

60 (1., the pepsin exhibits activity both 'dur-" ing and after pasteurization.

The proportion of the enzym to be added depends primarily upon the activity of the preparation, and secondarily upon the p rcentage of coagulable albumenoids in the beer; As a general rule, an enzym exhibitmg an activity of 1 6000, ma .be employed in the proportionof oneto barrel of thirty-one gallons of the proportion being increased or diminlshed according as the activit of the aratlon may vary from the a ove stan ard, and according to the percentage of coagulable albu'menoids contained in the beer. As

above stated, the enzym-is preferablyadded to the filtered or otherwlse clarifiedbee'r shortly before bottling, but the addition may be made if desired at any other suitable stage of the process, as for example during storage. .The addition'of the enzym preparationsin excessive proportions may render the beer again sensitive to cold.

.It is *a distinguishing characteristic. of beers and ales prepared in accordance with this invention and containing active proteolytic enzyms, that they are not only themselves far less sensitive to cold than most pasteurized beers, but they are capable of mparting this quality under proper cdnditlons to beers which are sensitive to cold fromrthe presence therein of proteid-mat-f ter.. For example, if a beer containing prove grams per beer or ale,

teolytic enzyms'be mixed with an equal or lesser volume of a beer which becomes tut.-

bid from the separation ofproteids when placed on ice, and the mixture kept for a suitable period at a temperature favorable to proteolysis, this mixture will be found thereafter to have acquired the property of remaining clear when subsequently chilled. This procedure constitutes, in the absence of interfering substances, as for example salts of tin or other heavy metals, a highly sensi-. tive test for the presence of these enzyms in a state of activity. A highly sensitive test for the presence of pepsin in a state of activity in beer or ale is by digesting or proteolyzing the hydrochloric acid-solution of the proteidknown as edestin; or ingeneral the enzyms in a state of activity can be detected by their proteolytic effects upon various albuminous substancesv or proteids,it being preferable to select for the detection of each enzym such proteids as are proven to be highly sensitive to its effects, as will be readily understood by those skilled in the art. The above tests are also applicable to the detection of proteolytic enzyms in 'va-.

rious media other than beer or ale, as for example in plant or animal secretions or in preparations made therefrom.

I do not herein claim broadly the prep-- aration of stable beers and ales by the addition thereto of proteolytic enzyms, or the beer or ale so treated, the said subject-matter, as well as the addition of such enzymatic preparations as may-be derived from malt, being claimed in my copending application, Serial Number 554,645, filed April 11, 1910, whereof the present application is a division; nor do I claim herein the treatment of beers and ales with papain, said subjectmatter being claimed in an application filed concurrently herewith.

I claim:

1. In the art of brewing, the step'which consists in adding to beer or ale, before bottling, a proteolytic enzym derived from the gastric secretions of mammals.

2. In the art of brewing, the step which consists in adding to beer or ale a proteolytic enzym derived from the gastric secretions of mammals, and subsequently pasteurlzing.

In testlmony whereof, I aflix my slgnature in presence of two witnesses.

LEO WALLERSTEIN.

Witnesses:

THos. GREEN, 0. C. ANGEVINE. 

